Previously portable or mobile telephone and communication units have been developed to perform several different tasks such as voice mail, facsimile mail, electronic mail, interactive voice response, automated audio text services, automated attenuated surface services electronic messaging services, radio paging services, speech recognition/speech synthesis, TDMF tone detection, voice recognition, interface of voice and data between public switched telephone network PSTN, the packet switched public data network, and portable telephone telephones. (For example, see U.S. Pat. No. 5,497,373.)
However, all of these units lack the capability to listen to public audio broadcast programs or stored digital audio programs from a compact disc player or cassette player while being able to simultaneously be alerted to incoming messages.
Many manufacturers sell headsets for portable cellular telephones on the market. Also different light-weight digital audio devices are available
However there is no system available where a digital cellular telephone and a digital audio device are combined to work integrally together.
U.S. Pat. No. 5,551,065 describes a solar-powered audio-entertainment device comprising a solar-powered cassette player, radio receiver or CD player in wireless connection with a headset. Such invention does not comprise a telephone and is not connected for wireless telecommunication.
A portable cordless telephone transceiver-RF-receiver is disclosed in U.S. Pat. No. 4,591,661. Such invention is a cordless telephone transceiver having a broadcast RF receiver. Use of this type of unit is restricted to a very limited area. It does not allow the listener free mobility because it is dependent on one RF transceiver and its area coverage is usually equal to one apartment.
U.S. Pat. No. 4,993,061 discloses a similar type cordless telephone as described in U.S. Pat. No. 4,591,661 except having a cassette player instead of a radio receiver. Both of these previous devices lack the complete portability which is typical for cellular telephone.
In U.S. Pat. Nos. 5,497,338 and 5,497,373, two personal communicators are disclosed. Personal communicators are capable to of sending and receiving faxes, e-mail and information either through a telephone line or via cellular network and to show messages on a display panel. These patents do not disclose an audio device or a headset.
A broadcast receiver and mobile telephone for motor vehicles is disclosed in U.S. Pat. No. 5,247,705. This invention is restricted to a vehicle environment and does not have a headset. It is designed to be installed to a vehicle permanently and it cannot be used outside of the vehicle.
A headset for use with a radiotelephone is described in U.S. Pat. No. 5,504,812. This headset can be used to carry on a phone conversation through an external speaker and microphone located in a headset. Such headset cannot be used to listen to an audio program while having the telephone in a stand-by mode. Also, the headset circuitry cannot produce an output tone when a push button is pressed, because the switch is connected in the ground return where it disconnects the earphone. The very best that this approach can do is to output a tone when the push button is released, not when it is pushed, which would be awkward. Every push-button telephone gives tones when the number keys are pressed, not when it is released. Without the beep each time the button is pushed, the user may loose track of the number of pushes or be uncertain as to whether or not the button was pushed far enough.
A headset for hands-free wireless telephone is disclosed in U.S. Pat. No. 5,596.638. Such invention is meant to be used only with a mobile telephone and cannot be used to switch operation between a telephone and an audio device.